Remove SignatureBinder.bindVariables

trinodb · Jul 30, 2020 · 212c36e · 212c36e
1 parent 376a6d3
commit 212c36e
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Showing 2 changed files with 25 additions and 13 deletions.
diff --git a/presto-main/src/main/java/io/prestosql/metadata/FunctionResolver.java b/presto-main/src/main/java/io/prestosql/metadata/FunctionResolver.java
@@ -52,15 +52,11 @@ public FunctionResolver(Metadata metadata)
 
     FunctionBinding resolveCoercion(Collection<FunctionMetadata> allCandidates, Signature signature)
     {
-        List<TypeSignatureProvider> argumentTypeSignatureProviders = fromTypeSignatures(signature.getArgumentTypes());
-
         List<FunctionMetadata> exactCandidates = allCandidates.stream()
                 .filter(function -> possibleExactCastMatch(signature, function.getSignature()))
                 .collect(Collectors.toList());
         for (FunctionMetadata candidate : exactCandidates) {
-            Optional<BoundVariables> boundVariables = new SignatureBinder(metadata, candidate.getSignature(), false)
-                    .bindVariables(argumentTypeSignatureProviders, signature.getReturnType());
-            if (boundVariables.isPresent()) {
+            if (canBindSignature(candidate.getSignature(), signature)) {
                 return toFunctionBinding(candidate, signature);
             }
         }
@@ -70,16 +66,20 @@ FunctionBinding resolveCoercion(Collection<FunctionMetadata> allCandidates, Sign
                 .filter(function -> !function.getSignature().getTypeVariableConstraints().isEmpty())
                 .collect(Collectors.toList());
         for (FunctionMetadata candidate : genericCandidates) {
-            Optional<BoundVariables> boundVariables = new SignatureBinder(metadata, candidate.getSignature(), false)
-                    .bindVariables(argumentTypeSignatureProviders, signature.getReturnType());
-            if (boundVariables.isPresent()) {
+            if (canBindSignature(candidate.getSignature(), signature)) {
                 return toFunctionBinding(candidate, signature);
             }
         }
 
         throw new PrestoException(FUNCTION_IMPLEMENTATION_MISSING, format("%s not found", signature));
     }
 
+    private boolean canBindSignature(Signature declaredSignature, Signature actualSignature)
+    {
+        return new SignatureBinder(metadata, declaredSignature, false)
+                .canBind(fromTypeSignatures(actualSignature.getArgumentTypes()), actualSignature.getReturnType());
+    }
+
     private FunctionBinding toFunctionBinding(FunctionMetadata functionMetadata, Signature signature)
     {
         BoundSignature boundSignature = new BoundSignature(
@@ -344,9 +344,8 @@ private Optional<List<Type>> toTypes(List<TypeSignatureProvider> typeSignaturePr
     private boolean isMoreSpecificThan(ApplicableFunction left, ApplicableFunction right)
     {
         List<TypeSignatureProvider> resolvedTypes = fromTypeSignatures(left.getBoundSignature().getArgumentTypes());
-        Optional<BoundVariables> boundVariables = new SignatureBinder(metadata, right.getDeclaredSignature(), true)
-                .bindVariables(resolvedTypes);
-        return boundVariables.isPresent();
+        return new SignatureBinder(metadata, right.getDeclaredSignature(), true)
+                .canBind(resolvedTypes);
     }
 
     private static class ApplicableFunction

diff --git a/presto-main/src/main/java/io/prestosql/metadata/SignatureBinder.java b/presto-main/src/main/java/io/prestosql/metadata/SignatureBinder.java
@@ -13,6 +13,7 @@
  */
 package io.prestosql.metadata;
 
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.VerifyException;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
@@ -116,7 +117,13 @@ public Optional<Signature> bind(List<? extends TypeSignatureProvider> actualArgu
         return Optional.of(applyBoundVariables(declaredSignature, boundVariables.get(), actualArgumentTypes.size()));
     }
 
-    public Optional<BoundVariables> bindVariables(List<? extends TypeSignatureProvider> actualArgumentTypes)
+    public boolean canBind(List<? extends TypeSignatureProvider> actualArgumentTypes)
+    {
+        return bindVariables(actualArgumentTypes).isPresent();
+    }
+
+    @VisibleForTesting
+    Optional<BoundVariables> bindVariables(List<? extends TypeSignatureProvider> actualArgumentTypes)
     {
         ImmutableList.Builder<TypeConstraintSolver> constraintSolvers = ImmutableList.builder();
         if (!appendConstraintSolversForArguments(constraintSolvers, actualArgumentTypes)) {
@@ -126,7 +133,13 @@ public Optional<BoundVariables> bindVariables(List<? extends TypeSignatureProvid
         return iterativeSolve(constraintSolvers.build());
     }
 
-    public Optional<BoundVariables> bindVariables(List<? extends TypeSignatureProvider> actualArgumentTypes, TypeSignature actualReturnType)
+    public boolean canBind(List<? extends TypeSignatureProvider> actualArgumentTypes, TypeSignature actualReturnType)
+    {
+        return bindVariables(actualArgumentTypes, actualReturnType).isPresent();
+    }
+
+    @VisibleForTesting
+    Optional<BoundVariables> bindVariables(List<? extends TypeSignatureProvider> actualArgumentTypes, TypeSignature actualReturnType)
     {
         ImmutableList.Builder<TypeConstraintSolver> constraintSolvers = ImmutableList.builder();
         if (!appendConstraintSolversForReturnValue(constraintSolvers, new TypeSignatureProvider(actualReturnType))) {